Or - I know - we could join an internet forum where knowledgeable people who know this stuff can answer our questions - no, wait, er.......
For a minute there I thought we may get some meaningful detailed answers on something that has only ever been the subject of knee jerks and smart comments like 'a solution in search of a problem', don't solve problems that don't exist' or 'if it ain't broke' etc. ad nauseam.
Maybe another day or if somebody else asks or summat. I thought my point about peak flow of piston being the same or even greater that the steady flow of the rotary was a good one and that in these days of pi$$ for fuel extra cooling oil coming down from the head would be a good thing.
""smart comments like 'a solution in search of a problem"" Blapper
I don't think that's a "smart" remark at all, and further, Roger backs it up with his experience.
The problems with the rotary have been properly addressed IMO with the answers above, from our most experienced and knowledgeable people (not me)
What exactly is the problem that you are trying to fix???
BTW IMO you should, of course, go ahead and let us know how it is after you've ridden it a lot. If you're going to run the back roads with the fast guys, make sure your breather exits behind the rear wheel. At ordinary riding, the excess oil should be no problem.
You're not drinking that wonderful Bordeaux tonight, are you?
Let's let an expert speak about Triumph oil pumps:
SHORT SUBJECTS Published in Vintage Bike September 2006 Copyright Keven Cameron 2006
Let’s update this classic old Triumph twin. Everybody’s doing it – start with an irresistible historic identity, add modern tech, and you’ve gotta have a winner, right? New Minis, Dreer Nortons – best of the old and new, all in one package. Look at this antique plunger oil pump on the poor old thing. What could they have been thinking? Why, it’s like trying to pressurize your home water system with a bicycle pump. Good luck with your shower up there on the second floor! We can do better – much better. Here’s a Gerotor oil pump conversion kit – out with James Watt’s 18th-century back-and-forth, in with modern continuous rotation. And gobs of oil pressure. More’s better, right? ROCK that gage! Hold on. Shouldn’t we examine the engine as a system, rather than just seeking to give it MORE of everything? The first point to make is that oil pump pressure does not support the load in a plain bearing. Long ago it was discovered that it is viscosity, combined with the motion of the bearing, that sweeps oil into the loaded zone. There, oil pressure reaches values (which have been measured directly) of several thousand psi. A moment’s thought shows this must be true. The mass of one piston, wristpin, rings, and con-rod is of the order of a pound, and the loaded area of the rod’s big-end bearing is of the order of a square inch. At a Triumph’s peak revs, maximum piston acceleration is about 2500Gs. Therefore average pressure in the oil film of the big-end bearing, resulting from this inertia force at TDC on the exhaust stroke, is of the order of 2500-psi. No engine oil pump generates even a tenth of that. Or, look at combustion load. A 650’s bore of 71-mm gives it a piston area of about six square inches. Peak combustion pressure, by rule-of-thumb, is one hundred times the compression ratio, so that gives us about 800-psi. That, times the piston area gives us a down-force on the big-end bearing of 4800 pounds. Therefore the oil pump’s job is just to push oil into the unloaded half of the bearing, while the pressure to support the load is generated on the other side of the bearing by viscosity and bearing motion. Oil enters the bearing through the crankpin oil hole(s) during that phase of bearing action when the oil hole is in the unloaded, or “clearance” part of the bearing. Typical oil film thickness in the loaded part of the bearing, at peak load, is something like .00006 inch. Bear in mind that in almost all automotive engines, oil enters the crank through drillings in the main journals. Oil pump pressure must force the oil into a main bearing, and then radially inward against centrifugal force, to reach the oilway that leads to a nearby rod journal. The usual 60-psi of an automotive oil system is there to overcome the pressure drops of (1) forcing oil around the main bearing groove to wherever the crankpin oil hole is, and (2) fighting its way inward against centrifugal force. A Triumph’s oil system doesn’t work that way, because it belongs to the elite company of “end-feeders”. Toward the end of the competitive life of Honda’s 15,000-rpm RC-45 Superbike, rod big-end trouble was encountered and higher oil pressure didn’t fix it. Time for end feed, which requires almost zero oil pressure to push oil into the center of one or both ends of the crank. Same for Rolls-Royce’s famed Merlin V-12 aircraft engine. Same for today’s 20,000-rpm F1 engines. End feed is cool. With it, Honda was able to cut RC45 oil pressure back to low levels and yet enjoy much improved big-end durability. Now consider what happens when we bolt on the SuperWhammy Double-Throwdown Oil Pressure Booster kit. With the relief valve set at some automotive level, the oil rushes to the delivery fitting at the crank end, where an ordinary oil seal handles the sealing task. Blooch! The new level of pressure turns that oil seal inside-out, making me think of the famous photo of Marilyn Monroe standing on the hot air grate. Oil spills into the timing case in large volume, hoping to find its way back to the scavenge before it wedges gears apart or gets a heat-generating merry-go-round ride from the crankshaft, possibly being fired up into the cylinders as well, as a special test of the oil rings’ ability to deal with a deluge. Oil everywhere! Meanwhile the rods are still happy because they are getting oil. All that an end-feed oil system needs is a metering pump that puts in oil as fast as the rod bearings squeeze it out at their edges. A funnel and a drip feed, properly adjusted, would do this job perfectly well on an end-feeder. It doesn’t require a pressure pump at all. Meanwhile the new SuperWhammy owner is distraught. He has low oil pressure when he thought he’d paid to see BIG NUMBERS ON THE GAGE. His engine is probably smoking as well. Lovely. Take it apart. Replace the seal. Listen humbly to the lecture from the experienced Triumph mechanic, who fiddles the relief valve to a pressure that the little crank end seal can handle. Now all the SuperWhammy is doing is holding the relief valve open farther than before. Modern science. It must be said that there are special uses for extra oil flow, above what is required to refill the bearing clearance every revolution. Plain bearings in heavy service may need additional oil flow for cooling, for when a bearing runs hot, the oil in it loses much of its viscosity. When that happens, the minimum oil film thickness may become so small that it is less than the surface roughness on bearing or journal. Result; even more heat generated, with possible surface damage. Fortune; danger. The usual way to fix this is to push more oil through the bearing, carrying away the heat and cooling it. As so many V8 engine builders have discovered, this doesn’t work unless the rods have sufficient side clearance. An engine is a system, and not a parts list. The rule here is, don’t solve problems that don’t exist. As long as the stock parts are in good fettle, the stock oil pump meters all the oil the big-ends need. If you operate your engine in some extreme fashion that requires special remedies, base those remedies on failures actually occurring in the engine, and not on vague threats appearing in advertisements in enthusiast magazines.
In a recent exchange of e-mails with a friend in the valve train business, I learned that special technologies used in racing can have unwanted side-effects. We love the lightness of titanium valves but we know this material makes a terrible wear surface. Therefore it has to be coated with some hard surface treatment. But what happens as that material generates super-hard wear particles? He also revealed that during valve spring surge, very large local forces can be generated which can fracture spring retainers made from even the highest-strength materials. What happens if small pieces of spring break off at the ends and enter the oil system? Likewise hard-faced cams are necessary to withstand the very high nose stress that occurs with short-timing, high torque valve events. Hard bits are known to crumble off of such cams. What happens to them? This awakened my memory of the interiors of Honda air-cooled racing engines of the classic 1960s. They had fine-mesh wire screening screwed and epoxied (the English say “Araldited”) into all oil return paths from cylinder head to crankcase. Aha! If bits of cam lobe hard-facing, valve-stem surface coating, or tapered valve spring ends get loose, they will be stopped before they can enter the oil system. When I was at the Indianapolis trade show I met an engineer in the valve spring business. He indicated that the finest spring wire now comes from a firm in Japan, and that one of the most respected fabricators making springs from that wire is located in Brazil. Engineering excellence is where the R & D money is being spent, and that is apparently not in the US. Time was, US-made S & W springs were the standard of excellence. Art Sparks (the ‘S’) had designed and built engines for champ car racing, prewar, and Tim Witham (the ‘W’) in the 1970s got interested in suspension dampers and just missed the damping revolution. Then spring manufacture shifted offshore to the German Schmitthelm outfit, suppliers to F1 before they went to pneumatic. I tell myself ‘get used to it – the US is #1 in a lot fewer things these days’. The tide comes in, the tide goes out. In the early years of the 20th-century, France was the internal combustion and metal alloys leader. US automakers imported expensive French nickel-alloy steel for crankshafts. Only as US factories created the mass market for autos in the 1920s (and in the 1930s for aviation) did the center of gravity of such research move here. And now, as the US auto industry struggles to stay alive, it’s moving on again. R & D goes wherever people are making the money to afford it. If you listen carefully, you can hear Boeing and Europe’s Airbus Industrie duke-ing it out for the airliner market, up at 35,000 feet. Mesdames et messieurs, place your bets. Business competition sounds noble in Kiwanis speeches, but actually encountering it is more like war. I asked my valve spring engineer how Japanese engines such as the 1983 Interceptor Superbike were able to avoid spring surge. Their springs had many more coils than the 3 _ turn “high frequency” springs originally proposed by German Peter Kuhn and manufactured so well by S & W. He replied, “They are progressive-wound from end-to-end”. Therefore as the valve lifts, the coils close up progressively. This causes the spring’s natural frequency to rise as it compresses. More recently, a fascinating conversation with an ex-Cosworth engineer revealed that they work from a toolbox of valve train remedies which they apply only as indicated. He scoffed at ‘beehive’ tapered springs – currently in high fashion – for he noted that this concept by itself solves little. Solutions come from careful observation of what is actually happening (through rig testing with instrumentation for valve motion recording), followed by application of appropriate remedies. There is no magic bullet – just dogged persistence and application of experience. Solutions will be different depending on how long the system is expected to operate without service. Every developer of racing engines has cams “under the bench” that made GREAT horsepower – but broke valve train parts too often. Web sites of cam and spring makers sometimes show high speed videos of spring action – with and without surge. Once the waves start banging rapidly from end-to-end, you can see the action speed up as the valve lifts, forcing coils closer together. Then you can see how super-strength retainers can be beaten apart by violent surge – the impacts are extremely rapid. This kind of problem is what sends smaller NASCAR teams to the Spintron for detailed analysis and advice – and causes the larger teams to have their own systems, which are booked solid with testing (Spintron is a system for motoring your engine at high speed by driving it with an electric motor, while laser-monitoring the motions of valve train parts). These problems aren’t new – Percy Goodman at Velocette used a strobe light to reveal the valve train problems of his first overhead cam KTTs in 1924-5. In the immediately previous pushrod era, TT riders carried spare pushrods tucked down a boot-top, with a rocker-arm depressor so they wouldn’t lose too many places each time one went flying. And if today’s computer modeling were a complete solution, race teams would not be making Spintron prosperous. Many years ago I bought a Harmon & Collins roller tappet cam kit for a Triumph 650. Dynamically, a roller tappet is just a small-radius special case of a radius tappet. Radius tappets are used rather than flat tappets when it is desired to increase maximum lift only. John Healy points out that pursuing this goal to the bitter end leads to the use of hollow-flank cam profiles (“They look like friggin’ guitars”, he says). Ever wonder why we don’t see more of these? The answer lies in the manufacturing process. In making conventional convex-flank cams, the grinder can use the biggest wheel that will fit in his grinder, and this acreage of sharp abrasive grains will eat a lot of metal between truings. Wheel economy is good, rib-eyes for dinner. To make a hollow-flank cam lobe, the wheel must have a radius smaller than the flank radius. Being so small, it requires truing often and goes away quickly. Costs are up, beans and rice for supper.
If the Triumph plunger pump is so great, when Doug Hele was laying out the triple engines, obviously with an eye towards existing Triumph and BSA design cues, having picked out things like Triumph's separate inlet and exhaust camshafts, mounted high to minimise pushrod length, did he choose a gear oil pump?
The triple oil pump is great - all else being equal, supplying at least one-third more pressure than the plunger pump (aiui, in line with the pressures reached in modern car engines). Moreover, with lengthened gears in the existing body, the flow rate increases to such an extent that you can safely run a triple engine on 10/40 instead of 20/50. I've never heard of a triple pump (or BSA twin pump) needing priming after an oil change, or any of the other problems that appear specific to the Morgo gear pump.
So, if another gear oil pump were available for twins, would we be missing the general advantages of gear pumps over plunger pumps because specifically the Morgo has problems the maker apparently chooses not to fix?
Thanks for taking the time to copy that article in, the first half is relevant to this thread and interesting.
So, it seems that Kevin Camerons' whole diatribe is based on the seal inverting because of the rotary pump? 80psi is 80psi whether it comes continuously or in squirts surely? Or is he really thinking that the seal inverts before the oprv controls the pressure? That point doesn't make any sense to me. Does it to anybody else?
Does anybody have anything to say about my points:
1/ The peak flow of the oil in the piston pump being the same or perhaps higher than the steady flow of the rotary?
2/ Extra oil coming down from the head will help control detonation (particularly relevant with modern fuel) and so is good?
3/ That the drive nut is in a random location on the half speed camshaft pinion and so this squirt is not arriving at a carefully thought out point in the engines cycle, also the time that the pump is 'breathing in' is at least as long as when it is pumping and during this time the ends are only relying on film strength as the oil continues to be squeezed out of the ends even while the piston pump is breathing in. It is the time that the engine is most at risk - especially if you are running 3134's and accelerating from low(er) revs?
I am very interested in redirecting the bypass, but I have to come up with a non-damaging way of extracting it.....
Morgo were seeing nearly 140psi on their test rig for their rotary pump in 1992. Although; I believe this has been reduced a bit in later versions according to John Healey in an earlier thread on this subject. Whereas they were claiming that the standard Triumph pump produced approximately 80psi which is the setting for the Pressure Relief Valve.
The max pressure of the pump is irrelevant because it is limited/bypassed by the oprv. The higher flow and is what we are talking about here and what it means/whether it is good or bad and how best to deal with it.
For me the attraction is smooth nature of the flow, the drawback is how best to deal with the extra rate of flow.
One thing that plain bearings like is a constant oil flow. Oil pressure is not indicative of a good flow necessarily as pressure is created by a resistance to flow. As has been shown here before some high power engines manage quite well on a relatively low oil pressure. I had a look in my favourite book Four-Stroke performance tuning by A Graham Bell (excellent value at £20 or less) and he gives a couple of examples where increasing flow (not pressure) reduced bearing failure.
With that in mind if we consider a Triumph pump vs Morgo then the Morgo should be better for bearing life as it provides a constant flow of oil. To answer Blapper’s question number 3 I can visualise that the Triumph pump output (and pressure) will be of a modified square wave form i.e. we have some flow for 50% of the time and we have none for the other (at 1000rpm that equates to 60ms).
Of course the above doesn’t mean that the Triumph pump is bad per se because plainly a Triumph engine will go many miles with no problems at all and so must work (all posters here with problems excepted).
BTW if anyone has connected an electrical oil pressure sensor (on a Triumph with standard oil pump) to an oscilloscope I’d be interested to see the output.
When I come to build my T100 I intend to fit a Morgo pump. I need a new pump and I haven’t read anything yet that persuades me otherwise in my situation. It’s just a matter of choice.
Of course some bearings get by on a mere whiff of oil, two-strokes for instance have zero oil pressure. My old four cylinder GSX1100 had an all roller bearing engine and the oil pressure on that was between 4 and 7 psi.
Also I believe the comments made here re aeroplanes are very relevant as both they and finned bikes use the same mechanism for cooling the engine. The fact that one engine is occasionally stationary and without cooling is irrelevant to the scheme of things. Again even though you have a prop that will push air through your engine fins aircraft still park facing into wind to aid cooling (among other reasons) when doing engine runs.
For Blapper’s question 1 about peak flow I suspect that the Morgo has a higher peak flow hence the problems with the pressure relief valve flow restriction. I don’t understand question 2.
1969 T100S under reconstruction GSX-R750K2 (having been rebuilt from a crashed wreck)
Blap: Kevin's point has little to do with inverting the oil seal, although this can become an issue as I have discussed many times. And not that the inversion of the seal actually leads to big end rod bearing failure, and at this point you should be aware of why it doesn't.
If it did we would have blown up thousands of Triumph 650 and 750 motors as nearly all of the early oriental crankshaft oil seals I tested would easily invert at or near the 80psi oprv setting. All that exta oil just increases the chances the rings will be flooded and let oil pass into the combustion chamber.
Stuart: You didn't read Kevin's article, be honest, did you. If you did you missed the entire point. Kevin isn't a light weight in the motorcycle engineering world. This isn't a rant by a crazed enthusiast! I consider it a privelage to be able to publish a magazine that he thinks enough of to share his knowledge.
There are a different oil pressure requirements for "side feed" and "center feed" crankshafts: a. Pumps used to maintain pressure of "side feed" crankshafts, like Tridents, where the pump has to overcome the centrifigal force trying to push the oil back into the pump; b. and pumps used to feed "center feed" crankshafts where the outward force actually pulls the oil into the rod bearings.
It is this natural pumping action of the rotating crankshaft that keeps the side feed 650 and 750 from outright rod bearing failure when the crank seal inverts and oil pressure falls to near zero.
Blapper: As the pressure builds up in the cavity behind the crank seal and oprv when you first start the motor, and pressure is building, you can see some pulsing. But the spring in the oprv effectively dampens the pumps pressure pulse and if there is any fluctuation to be so slight, if at all, not be perceptable on the oil pressure guage. And so what if it did, there is enough oil, and then some, to supply anything the Triumph crankshaft might require.
Now there might be a reason one would want to use the Morgo rotary (IMHO Their piston pump is the BEST on the market!!!!). Unlike a roller bearing big end bearing, plain bearing big ends use oil to cool the parts. Without the constant flow of oil through the plain bearing it would heat up and sieze. But you cannot just increase the pressure (which you don't anyway with the Morgo rotary as the oprv (and indirectly the crankshaft oil seal) limits it to 80 pounds to increase the amount of oil flowing through the rod bearing.
And here is where most miss the reason for using a "high volume" Morgo pump. To actually increase the flow of oil through the rod bearing its clearance on the crankshaft MUST BE increased. Failing to do this and all that exta volume is by-passed back to the oil tank by the oprv.
To accomplish "extra" flow performance engine builders increase the rod bearing clearance in two ways: 1. By increasing the rod bearing clearance on the crankshaft by using a special larger i.d. bearing shells or grinding the crankshaft bearing surface smaller. 2. Or by using a special bearing where the plain rod bearing surface is oval. Normal clearance top to bottom but additional clearance on the parting surface or side-to-side. Without compensating for the increased volume of oil provided by either of these choices oil pressure would drop. Thus performance engine builders provide a pump with increase volume to compensate.
There is one other consideration one must take into acount when increasing the rod bearing clearance: the oil must have some where to go to get out of the rod. One must consider if the rod's side-to-side clearance is enough to allow all this extra oil to escape or all of the work and expense is for naught. It is not unusual to have to increase the clearance by maching some metal from the big end sides of the rod.
Ahh, you say I get it, but remember all of this "extra" oil you now provided to cool the rod bearing journal is being splashed up onto the cylinder walls. Have you asked the question: will my rings handle it? My experience indicates you should!
So thinking about the Morgo rotary doesn't stop with opening up the holes in the oprv, opening up the holes in the crankcase or making sure the oil seal will handle the pressure at cold start up or high rpm! If you are going to use the potential of Morgo's rotary pump's flow you better start thinking about all of this as a system, not a bunch of parts.
Now, the Morgo rotary pump is made to a high standard, but IMHO the average owner will get little from the experience of owning one and I find the hassles, including the potential of loosing prime when changing oil on o.i.f. models, and the stress the extra oil puts on the rings, not to be worth it. That said I think the Morgo piston pump is the best pump for a Triumph twin on the market and is good value for the money spent!
AND I AM NOT RECOMMENDING any of these bearing, crankshaft, or connecting rod changes for the average owner or a street bike!!!! This stuff is best left to the professionals. John
Blapper, I note that you regard my post as a "smart comment". Feel free to do so, I wrote what I believe, based on experience.
Stuart, I'm not saying the plunger job is a great design, but it has proven itself to be adequate in these engines. Why buy something you don't need? The priming issue, as I understand it, is OIF only, when you remove the bottom cover and let the oil pipe drain out. Shouldn't happen on an earlier bike.
I tried a Morgo pump on my 72 Tiger 825cc bike (Routt kit). The reason I did it was because the stock Triumph pump had worn out. As previously mentioned, the design of the Triumph pump is not as robust as the gear type pumps on the BSA so I thought that the gear design of the Morgo would be more reliable than the piston pumps.
Well, I have to agree with the experts here, DON'T GET ONE!!
1) The oil pressure issues combined with the increased crank pressure from the Routt kit caused a fountain of oil to come out fo the breather. 2) I ultimately lost prime and seized the engine on the freeway!
Back to the piston pump and the "smart" comment by Jack Wilson and others - if it ain't broke, don't fix it.
The Triumphs pumping action would not look like a square wave, it is worse than that - the piston is driven by a rotating peg so the first and last parts of the action are slower, in fact slowing to, and accelerating from, zero - where it rests for half a camshaft revolution.
With this in mind, my question 1 relates the peak flow at the FASTEST part of the pump pistons travel to the steady state flow of the Morgo at the same engine speed. I believe there to be little difference and if the holes can cope with it at that speed intermittently...
My question two links to a current thread here about John Michl's freshly trashed motor. The thread brings up the problems with heat in the engine during break in using current fuels, and I am alluding to the extra flow cooling the top end more than the standard pump. The modern pi$$ we call fuel is the only reason I can't follow John H's an@logy about aircraft and motorcycle engines.
I follow and agree with most of what is said in Kevins article and your reply, but not all.
You are saying that the compliance of the crankshaft seal turns the pulsed supply into a steady flow?
Forgive me pasting in this, but:
the oil rushes to the delivery fitting at the crank end, where an ordinary oil seal handles the sealing task. Blooch! The new level of pressure turns that oil seal inside-out, making me think of the famous photo of Marilyn Monroe standing on the hot air grate. Oil spills into the timing case in large volume, hoping to find its way back to the scavenge before it wedges gears apart or gets a heat-generating merry-go-round ride from the crankshaft, possibly being fired up into the cylinders as well, as a special test of the oil rings’ ability to deal with a deluge. Oil everywhere! Meanwhile the rods are still happy because they are getting oil. All that an end-feed oil system needs is a metering pump that puts in oil as fast as the rod bearings squeeze it out at their edges. A funnel and a drip feed, properly adjusted, would do this job perfectly well on an end-feeder. It doesn’t require a pressure pump at all. Meanwhile the new SuperWhammy owner is distraught. He has low oil pressure when he thought he’d paid to see BIG NUMBERS ON THE GAGE. His engine is probably smoking as well. Lovely. Take it apart. Replace the seal. Listen humbly to the lecture from the experienced Triumph mechanic, who fiddles the relief valve to a pressure that the little crank end seal can handle. Now all the SuperWhammy is doing is holding the relief valve open farther than before. Modern science.
Very humorously put, but a bit 'tabloid' for me.
If I unnerstand it correctly, Kevin Cameron is saying that the mechanic has to modify the oprv to a lower pressure because of the rotary oil pump? Sorry, but I can't see that.
I realise I must be being thick here, but whichever pump you choose, it is capable of delivering more pressure than the oprv is set to bypass at, so what is it about the characteristics of the way the rotary presents the oil to the oprv that makes the seal invert (and I will use a Pioneer seal), whereas the piston pump doesn't?
I'm running out of different ways to ask the same question and up until now haven't heard an answer I can agree with. I will drop this project as quick as a flash if somebody can explain to me why It's a bad idea or I have an epiphany and see the light - I don't want to have any problems. There seem to be people out there who are using these pumps and not having a problem but may not be joining in because they can't be bothered or something. People have said in the past that they've used the rotary without problems and for high mileage, but that is just what I recall so is useless as hearsay.
I also attach some weight to people saying I tried it but dropped it, but without an explanation that holds water, I see it as - possibly- their failure because they were looking for a bolt-on goodie with no problems (now that would be nice) and when they got problems they just dropped it.
Note I am not saying I'm better/cleverer than anybody else here, maybe I'm stubborn but I would just like to know why.
You are saying that the compliance of the crankshaft seal turns the pulsed supply into a steady flow?
No, I am saying that the oprv spring would act to is dampen the pulse of the oil pump, and if there was any pulse that is not an issue with "center fed" crankshafts.
Listen: 1. It is not an issue about quality! The Morgo rotary pump is a well made part. 2. It isn't an issue about oil flow, there is more oil availbe from the plunger pump than could ever flow through the clearance in the existing rod bearings without increasing the oil pressure itself. 3. It isn't an issue that you cannot use the Morgo rotary pump, with its potential (and potential is the right word to use here) of providing more flow if it had some where to go. In a stock motor it doesn't! 4. It isn't that you are a bad person for buying a Morgo rotary pump or its a bad idea, you aren't and it isn't as such! Heck I bought, installed and used more than one. 5. It is that it is answer to a problem that doesn't exist and without further modifications to the engine, besides modifications to the oprv AND crankcase introduces other problems that were non-existant before the pump was installed - loosing prime and piston ring oil control when you actually make the needed modifications to the rod bearing/crankshaft clearance to use the extra oil. 6. Will anything bad happen when you finaly start that project motor - no!
But all this ignores, as did Tony Waterworth when we brought it to his attention, that a lot of the seals sold for use on the crankshaft are not designed to be used in this application. I learned this 30 years ago when we ordered 30,000 of these seals from Taiwan which would invert at normal pressures. Many of the seals sold today aren't much better at doing the job. Thus, Kevins reference to "Blooch".
Kevin is writing to get you to think. His writing style in magazines is to try to get you to understand, or at least recognize, complex engineering concepts. If you want to talk in engineering speak he is more than willing and capable. I feel no complusive need to defend Kevin.
AND Blapper you need to read my comments again about the discipline in the small air craft business - if we had such factory support and oversite we would not be dealing with seals that can be bought for short money and weren't up to the job. John
Blapper, just use yours and then tell us how you feel.Im going to tell you for a stock bike you waisted your money.I know I don;t want all that oil dumped on my crankshaft. I go to great lenghts to keep tons of oil off the crank.I will use mine but have to do more home work.There is a simple way to bypass the oil from your prv back to your tank as john showed me many years ago and mabe he can tell you better then I. The fitting on the dome nut and cut more bypass groves in plunger body. If I know how to post a picture I would.:)
Tim Joyce sponsors D@D cycles Works shocks Glass from the past
Hi Tim - why aren't you on vacation??? You just can't keep away can you!
I have been giving that some thought myself and am surprised to hear that I may have come up with the same idea you just mentioned. Maybe John can expand - if he isn't too fed up with me!
I really am skeptical about this seal inversion business but I am thinking that machining slots instead of drilling holes is the answer so that the coil spring in the oprv doesn't have to compress too much (thereby causing more oil pressure) to shift the excess flow. What else could cause it but more of the holes having to uncover to reveal sufficient cross sectional area to cope with the flow?
On the subject of waisted money, don't forget the 'money back if not completely satisfied' guarantee that Morgo gives
<I am thinking that machining slots instead of drilling holes> Blapper I suppose the ideal is to modify the PRV so that it moves the same amount with the Morgo as it did with the Triumph. So, if the Morgo provides twice the flow (does anybody know?) and if the PRV has two holes as standard then you need four. Keep it simple.
Better still, get your bike running and let us know!
1969 T100S under reconstruction GSX-R750K2 (having been rebuilt from a crashed wreck)
John: Thanks for the Kevin Cameron article. Excellent And thanks to all for good discussion. But it now appears that mods are needed to handle to increased oil flow. I will pass it along. And I'll stick with my std plunger.